The present invention relates to a drive control apparatus for a motor driven vehicle particularly a small tractor, golf cart, or other small engine propelled vehicle. The present invention is particularly useful for a power propelled vehicle carrying power driven means for cutting the grass of an athletic field or the like in a narrow strip while simultaneously applying marking material to the strip to provide boundary lines and other lines thereon. Such a vehicle is described in detail in U.S. Pat. No. 3,052,077.
Although the line marking machine described in the aforesaid patent works fine in cutting a long line, it is limited in its ability to cut and mark short line segments because the power control apparatus which couples the engine to the drive wheels cannot be controlled to provide precision starts and stops for the vehicle while allowing the engine to run at full speed to power the grass cutter at its most efficient cutting speed. Also, the line marking machine is not adapted for reverse movement.
Accordingly, an object of the invention is to provide a power control mechanism which allows a variable forward speed and reverse control of a motor driven in which the motor must run at a high constant output speed, such as in the line marking vehicle described in the above-mentioned patent.
The drive control apparatus according to the present invention provides an operator with both precision starts and stops of the vehicle while allowing the engine to run at a predetermined full speed to power, in the case of the above-mentioned line marking apparatus, the grass cutter at its most efficient speed. Thus, when the drive control apparatus of the present invention is used with the line marker, an operator may creep up to and stop at the beginning of a line to be marked, begin cutting and/or marking at a precise point while moving forward at the full rate of speed of the engine of the vehicle, travel to the opposite end of the line, slow down and stop. Thereafter, the cutter may be raised and the vehicle move forward to the next line. If the operator overshoots a line, the reverse control mechanism allows him to back-up before engaging the cutter.
Since it is possible that an absentminded operator may engage the control apparatus of the vehicle while disembarking from the same, the present invention also provides a unique seat disengagement apparatus which prevents vehicle run away by forcing the power control apparatus to remain in its neutral or rest running position unless the seat of the vehicle is occupied.
These and other objects of the present invention will become apparent from the following detailed description of the invention when read in conjunction with the accompanying drawings.